Those who can't get enough of Viggo Mortensen will relish the actor's dual role in this otherwise tepid Spanish-language drama by first-time writer-director Ana Piterbarg.

Those who can’t get enough of Viggo Mortensen will relish the actor’s dual role in “Everybody Has a Plan,” wherein identical twin sibs — one a blood-spittingly ill and chainsmoking beekeeper, the other a classy but listless hubby — switch places. Others, however, will wish that Mortensen’s two parts had factored in a pic more compelling than this tepid Spanish-language drama by first-time writer-director Ana Piterbarg. Slow pacing, thinly drawn characters, a limp climax and humorless tone all undermine the effects of lush shooting on a tiny island off the Argentine coast. Commercial prospects Stateside look limited.

The Argentina-born Mortensen (who also serves as a producer) first appears as the terminally cancerous Pedro Sovto, who augments his modest bee-tending income by providing muscle to Adrian (Daniel Fanego), a local thug. Piterbarg does a fine job early on of keeping the proceedings off-kilter, as Mortensen’s next appearance as a clean-cut Buenos Aires pediatrician seems part of a flashback — until it’s revealed that the doc is Pedro’s unhappily married twin brother, Augustin, who suddenly announces to his wife, Claudia (Soledad Villamil), that he wants nothing more to do with their plans to adopt.

In other words, each brother is looking for a way out, leading the viewer to expect something twistier — or at least more intriguing — than what transpires at a snail’s pace back on the island. Suffice to say that Pedro’s pretty beekeeping assistant, Rosa (Sofia Gala Castaglione), can’t believe how much her colleague has improved his manners, and that the inevitable showdown with kidnapper Adrian, menacingly played by Fanego, comes as too little, too late in a two-hour would-be thriller.

Mortensen invests his two parts with a familiar soulfulness that Piterbarg’s screenplay doesn’t much reward. Far and away the stronger character happens, ironically, to be the weaker one, as Pedro’s slow progress to his grave gives the pic a modicum of human interest. Editing regularly allows scenes to overstay their welcome; shooting by Lucio Bonelli is richly detailed and atmospheric where the rest of the movie is not.